From: Marco Elver <elver@xxxxxxxxxx> To help catch ABI breaks at compile-time, add compile-time assertions to verify the siginfo_t layout. Unlike other architectures, sparc64 is special, because it is one of few architectures requiring si_trapno. ABI breaks around that field would only be caught here. Link: https://lkml.kernel.org/r/m11rat9f85.fsf@xxxxxxxxxxxxxxxxx Link: https://lkml.kernel.org/r/20210429190734.624918-1-elver@xxxxxxxxxx Link: https://lkml.kernel.org/r/20210505141101.11519-1-ebiederm@xxxxxxxxxxxx Suggested-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> Acked-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> --- arch/sparc/kernel/signal32.c | 35 +++++++++++++++++++++++++++++++++++ arch/sparc/kernel/signal_64.c | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 69 insertions(+) diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c index e9695a06492f..65fd26ae9d25 100644 --- a/arch/sparc/kernel/signal32.c +++ b/arch/sparc/kernel/signal32.c @@ -745,3 +745,38 @@ asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp) out: return ret; } + +/* + * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as + * changes likely come with new fields that should be added below. + */ +static_assert(NSIGILL == 11); +static_assert(NSIGFPE == 15); +static_assert(NSIGSEGV == 9); +static_assert(NSIGBUS == 5); +static_assert(NSIGTRAP == 6); +static_assert(NSIGCHLD == 6); +static_assert(NSIGSYS == 2); +static_assert(offsetof(compat_siginfo_t, si_signo) == 0x00); +static_assert(offsetof(compat_siginfo_t, si_errno) == 0x04); +static_assert(offsetof(compat_siginfo_t, si_code) == 0x08); +static_assert(offsetof(compat_siginfo_t, si_pid) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_uid) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_tid) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_overrun) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_status) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_utime) == 0x18); +static_assert(offsetof(compat_siginfo_t, si_stime) == 0x1c); +static_assert(offsetof(compat_siginfo_t, si_value) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_int) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_ptr) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_addr) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_trapno) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_addr_lsb) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_lower) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_upper) == 0x18); +static_assert(offsetof(compat_siginfo_t, si_pkey) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_perf_data) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_perf_type) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_band) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_fd) == 0x10); diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index a0eec62c825d..a58e0cc45d24 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -556,3 +556,37 @@ void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long user_enter(); } +/* + * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as + * changes likely come with new fields that should be added below. + */ +static_assert(NSIGILL == 11); +static_assert(NSIGFPE == 15); +static_assert(NSIGSEGV == 9); +static_assert(NSIGBUS == 5); +static_assert(NSIGTRAP == 6); +static_assert(NSIGCHLD == 6); +static_assert(NSIGSYS == 2); +static_assert(offsetof(siginfo_t, si_signo) == 0x00); +static_assert(offsetof(siginfo_t, si_errno) == 0x04); +static_assert(offsetof(siginfo_t, si_code) == 0x08); +static_assert(offsetof(siginfo_t, si_pid) == 0x10); +static_assert(offsetof(siginfo_t, si_uid) == 0x14); +static_assert(offsetof(siginfo_t, si_tid) == 0x10); +static_assert(offsetof(siginfo_t, si_overrun) == 0x14); +static_assert(offsetof(siginfo_t, si_status) == 0x18); +static_assert(offsetof(siginfo_t, si_utime) == 0x20); +static_assert(offsetof(siginfo_t, si_stime) == 0x28); +static_assert(offsetof(siginfo_t, si_value) == 0x18); +static_assert(offsetof(siginfo_t, si_int) == 0x18); +static_assert(offsetof(siginfo_t, si_ptr) == 0x18); +static_assert(offsetof(siginfo_t, si_addr) == 0x10); +static_assert(offsetof(siginfo_t, si_trapno) == 0x18); +static_assert(offsetof(siginfo_t, si_addr_lsb) == 0x18); +static_assert(offsetof(siginfo_t, si_lower) == 0x20); +static_assert(offsetof(siginfo_t, si_upper) == 0x28); +static_assert(offsetof(siginfo_t, si_pkey) == 0x20); +static_assert(offsetof(siginfo_t, si_perf_data) == 0x18); +static_assert(offsetof(siginfo_t, si_perf_type) == 0x20); +static_assert(offsetof(siginfo_t, si_band) == 0x10); +static_assert(offsetof(siginfo_t, si_fd) == 0x14); -- 2.20.1
